The objectives of this project are (1) to develop reliably effective and efficient techniques for teaching patients to control their own heart rates so as to achieve clinically significant changes; (2) to develop methods of insuring the transfer of the self-control, learned and demonstrated in the laboratory, to the patients' natural environment; and (3) to utilize the knowledge gained in achieving the first two objectives to develop similarly effective and efficient techniques for teaching patients to control their own blood pressure. The project will begin by optimizing the operant conditioning of heart rate procedure of Peters, Scott and Gillespie (1971) through a series of studies on normal subjects. The optimized procedure will then be given a full scale clinical trial on chronically anxious patients suffering from tachycardia; methods for obtaining transfer will be developed using these patients. The optimized procedure will be used with patients suffering from other cardiac disorders under appropriate circumstances. The blood pressure control procedure of Shapiro et al (1970) will be adapted to the optimized procedure and a full scale clinical trial on patients suffering from essential hypertension will be conducted.